水果 网站源码,wordpress win10主题,qq代刷网站社区建设,在什么网站做贸易好android简单登陆和注册功能实现SQLite数据库学习发布时间#xff1a;2018-07-04 17:23,浏览次数#xff1a;1027, 标签#xff1a;androidSQLite这里我只是建立了一个用简单的存储用户名和密码的表单MyDBHelper.javapublic class MyDBHelper extends SQLiteOpenHelp…android简单登陆和注册功能实现SQLite数据库学习发布时间2018-07-04 17:23,浏览次数1027, 标签androidSQLite这里我只是建立了一个用简单的存储用户名和密码的表单MyDBHelper.javapublic class MyDBHelper extends SQLiteOpenHelper { public static finalString CREATE_USERDATAcreate table userData( id integer primary keyautoincrement, nametext, password text); private Context mContext; publicMyDBHelper(Context context, String name, SQLiteDatabase.CursorFactorycursorFactory,int version){ super(context,name,cursorFactory,version); mContextcontext; }public void onCreate(SQLiteDatabase db){ db.execSQL(CREATE_USERDATA);}public void onUpgrade(SQLiteDatabase db,int oldVersion,int newVersion){ //onCreate(db); } } 注册Main2Activity.java public class Main2Activity extends AppCompatActivity {private MyDBHelper dbHelper; Override protected void onCreate(BundlesavedInstanceState) { super.onCreate(savedInstanceState);setContentView(R.layout.activity_main2); dbHelper newMyDBHelper(this,UserStore.db,null,1); } public void logon(View view){//SQLiteDatabase dbdbHelper.getWritableDatabase(); EditTexteditText3(EditText)findViewById(R.id.editText3); EditTexteditText4(EditText)findViewById(R.id.editText4); String newnameeditText3.getText().toString(); StringpasswordeditText4.getText().toString(); if(CheckIsDataAlreadyInDBorNot(newname)) {Toast.makeText(this,该用户名已被注册注册失败,Toast.LENGTH_SHORT).show(); } else { if(register(newname, password)) { Toast.makeText(this, 插入数据表成功,Toast.LENGTH_SHORT).show(); } } } //向数据库插入数据 public boolean register(Stringusername,String password){ SQLiteDatabase db dbHelper.getWritableDatabase();/*String sql insert into userData(name,password) value(?,?); Objectobj[]{username,password}; db.execSQL(sql,obj);*/ ContentValues valuesnewContentValues(); values.put(name,username); values.put(password,password);db.insert(userData,null,values); db.close(); //db.execSQL(insert intouserData (name,password) values (?,?),new String[]{username,password}); returntrue; } //检验用户名是否已存在 public boolean CheckIsDataAlreadyInDBorNot(String value){SQLiteDatabase dbdbHelper.getWritableDatabase(); String Query Select * fromuserData where name ?; Cursor cursor db.rawQuery(Query,new String[] { value}); if (cursor.getCount()0){ cursor.close(); return true; } cursor.close();return false; } } 登陆MainActivity.java public class MainActivity extends AppCompatActivity {private MyDBHelper dbHelper; private EditText username; private EditTextuserpassword; Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState); //requestWindowFeature(Window.FEATURE_NO_TITLE);setContentView(R.layout.activity_main); dbHelper new MyDBHelper(this,UserStore.db,null,1); } //点击注册按钮进入注册页面 public void logonClicked(View view){Intent intent new Intent(MainActivity.this,Main2Activity.class);startActivity(intent); }//点击登录按钮 public void loginClicked(View view) { username(EditText)findViewById(R.id.editText2); userpassword(EditText)findViewById(R.id.editText); String userNameusername.getText().toString(); String passWorduserpassword.getText().toString();if (login(userName,passWord)) {Toast.makeText(MainActivity.this, 登陆成功(ZY111), Toast.LENGTH_SHORT).show(); }else { Toast.makeText(MainActivity.this, 登陆失败, Toast.LENGTH_SHORT).show(); } }//验证登录 public boolean login(String username,String password) { SQLiteDatabase db dbHelper.getWritableDatabase(); String sql select * from userData wherename? and password?; Cursor cursor db.rawQuery(sql, new String[]{username, password});if (cursor.moveToFirst()) { cursor.close(); return true; }return false; }